server side SignalR with WebAPI..

http://drew5.net/code/real-time-communication-to-xamarin-app-via-signalr-and-azure-api-app-services/ https://forums.xamarin.com/discussion/11734/what-is-the-right-way-to-get-signalr-working-on-xamarin-mobile-apps https://www.simple-talk.com/dotnet/net-development/using-signalr-to-create-mobile-applications/ http://gregshackles.com/building-a-real-time-photo-gallery-with-xamarin-signalr-azure-and-webapi/ https://github.com/schneidenbach/Xamarin-Forms-and-SignalR-Example http://www.c-sharpcorner.com/uploadfile/b1df45/chat-application-using-asp-net-signalr/ Please refer this blogs